“Never interrupt your enemy when he is making a mistake.”

“Gentlemen, when the enemy is committed to a mistake we must not interrupt him too soon.”

“Never interrupt someone who is making a mistake.”

“.., by universal custom, your enemy is never more polite than when he is planning or has planned your destruction.”

“He who never makes a mistake never makes anything. It's part of learning the job.”

“Drama is based on the Mistake. I think someone is my friend when he really is my enemy, that I am free to marry a woman when in fact she is my mother, that this person is a chambermaid when it is a young nobleman in disguise, that this well-dressed young man is rich when he is really a penniless adventurer, or that if I do this such and such a result will follow when in fact it results in something very different. All good drama has two movements, first the making of the mistake, then the discovery that it was a mistake.”